From the Blue State Digital statement:

"Pursuant to company policy regarding outside political work or commentary on behalf of our clients or otherwise, Mr. de Vellis has been terminated from Blue State Digital effective immediately."

Don't most companies have these kind of prohibitions on outside work? If I worked in a creative department of an advertising company that had McDonald's as a client and made a clever YouTube clip showing the Burger King as Joseph Stalin that I produced in my free time would that be OK with my employer?

Phil deVellis could have remained anonymous and kept his job. He didn't and will have better long term prospects because of the success of the 1984 ad. I don't see why it's any big deal that he left/was asked to leave by Blue State Digital.